Final Exam Flashcards
Coxsackie A and B
Coxsackie viruses A & B = picornaviridae enterovirus, spread via fecal oral route
enters body via URT, oropharynx, intestinal tract
Coxsackie A16
Herpangina = vesicles on soft palate and fuaces
Aka hand, foot and mouth disease
Hand, foot and mouth disease
S/S = rash/ blisters on hands, palate or feet, fever
Self resolves
Coxsackie B
Causes Bornholm myocarditis aka pleurodynia aka devil’s grip
S/S = upper resp. sx, fever and ONE SIDED chest pain
Self resolves
Coronaviridae
Coronavirus, SARS, Rhinovirus, common cold
transmission via resp. droplets
2nd most common cause of cold virus
peaks in winter and early spring
SARS (severe acute respiratory syndrome) caused by special species of coronaviridae
Bind to ICAM receptor
Labile in acid, replicate at lower temp (33 degrees Celsius)
Treat with Pleconaril (bind hydrophobic pocket) or Methylisoxazole compounds (interfere with uncoating process)
CMV
Retinitis in AIDS
Replicate in ductal epithelial cells promoting excretion of virus in most bodily fluids
transmitted in utero (most common), milk, sex, blood
cytomegalic inclusion disease = in utero infx, fatal
persistent, latent infx
Reactivated in people w/ AIDS as CMV retinitis or in transplant pts as interstitial pneumonitis
usually seen when CD4+ levels most common opportunitic infx in AIDS pts
S/S = pizza pie retinopathy
Treat w/Ganciclovir (synthetic analogue of dGTP terminating elongation of viral DNA) and Foscarnet (inhibits pyrophosphate binding site on viral DNA polymerase)
HIV
HIV (mode of transmission; opportunistic infections & other diseases, retinitis, Kaposi etc)
retroviridae lentivirus
transmission via blood, sex, vertical (get directly from mom)
AIDS when CD4+ levels
HIV Staging
Pathogenesis
Stage 1 = virus affects CD4 T cells and dendritic cells.
Stage 2 = infected cells transported to lymph nodes and spleen. Large scale replication occurs here which leads to primary VIREMIA
Stage 3 = Immune reaction. Some of virus will be neutralized by Abs, Some cells will be killed by cells infected by virus. Virus enters clinical latency.
Stage 4 = Latent phase. Virus remains in lymphoid organs. Shields from the body IS. Continues to reproduce here. Secondary Viremia
CD4 T cell counts steadily decline due to active replication and T cell destruction
Stage 5 = AIDS = Destruction of lymphoid tissues, dendritic network breakdown and depletion of CD4+ cells.
Infection, primary viremia, immune response, latency, secondary viremia, and then AIDS
HSV 1 & 2
Cold sores = enveloped large dsDNA, enters via mucous membranes or skin breaks
HSV1 = common, oral via trigeminal nerve infection
HSV2 = STD on genitals, anal, oropharynx, genital via sacral nerve infection
neonate infection is lethal
Skin,eye and Mouth Disease= SEM
CNS Disease= encephalitis/Meningitis (mostly HHV1)
Disseminated Disease -> Death
Herpetic Whitlow=painful lesion on digits
Tx: Acyclovir (Nucleotide Analog) inhibits DNA synth, requires viral thymidine kinase
TK mutation= no Acyclovir activation
can treat herpes keratitis and its complicated dendritic corneal ulcer
Hep B and C
Oncogenic - Hep B and C -> Primary Hepatocellular carcinoma
Hep B - enveloped dsDNA, uses RT + RNA intermediate
spreads via saliva, sex, blood, mother -> milk
presents as jaundice, dark urine, pale stool-> affects liver
Tx: IFN-a for chronic disease
Vaccine booster
Drugs target polymerase + RT (Lamivudine + famiciclovir)
Hep C - positive stranded RNA, enveloped, flaviviridae
via blood to blood, sexual, NOT VIA MOSQUITO
Iatrogenic = by medical or dental exposure
slam dancing
no vaccine
Hep A
Hep A = member of picornavirus
via oral/fecal route, undercooked shellfish
enters blood stream via lining of intestinal tract
migrates to liver parenchymal cells
presents as jaundice, never chronic
vaccine available
EBV
HHV-4, dsDNA
infects B cells (binds to CR2 complement receptor) and epithelial cells of oropharynx
Transmission= salvia (kissing disease), blood -> seen during 1st year of college
over reactive immune system -> Mono OR
weak immune system -> Burkitt Lymphoma
can also lead to Harry Leukoplakia = white vertical folds along tongue
HPV
HPV (warts, cervical cancer, vaccine) - papoviridae, naked dsDNA, circular
oncogenic -> Cervical Cancer, head + neck tumors
Plantar warts (painful), condyloma acumination
via direct contact, sexual contact, birth
Prevented via vaccine (Gardasil)
Adenovirus
hexahedral, naked double strand DNA
via fecal/oral, crowded areas (classroom, military)
infects epithelial cells lining oropharynx, respiratory and GI
presents as Pink Eye, along with GI problems and pharyngitis/acute resp disease
Hemorrhagic Cystitis= more common in boys from swimming
supportive treatment only
Parvovirus B19
Parvoviridae, DNA virus (+), naked ssDNA
Icosahedral symmetry, replicate in nucleus
slapped cheek fever, Lacy body rash+ facial rash.
immature RBC’s infected -> aplastic crisis (sickle cell patients)
Transmission: respiratory aerosols+ maternal-fetal. 5th pediatric disease
VZV
HHV-3, enveloped DNA virus (+), dsDNA, Icosahedral symmetry, replicated in nucleus.
Transmission: very contagious, spread respiratory aerosols + skin contact.
1° viremia starts in respiratory tract spreads to blood & lymphatics.
2° goes to skin -> vesticulopapular rash = chicken pox
Latent in dorsal root ganglion -> can spread along neural pathways to the skin = shingles
Chicken pox (varicella): maculopapular rash (severe on trunk and extremities) -> can lead to necrotizing fasciitis (caused by strep and staph aureus secondary to chicken pox)
Zoster/shingles: affects only one side of the body because a single dermatome is affected (severe pain in nerves precedes lesions
Vaccine: VZV vaccine (live, attenuated)
Smallpox
poxviridae
complex structure -> tubular structured enveloped, (-) sense linear dsDNA virus,
has polymerase, brick shaped nucleocaspid.
Core: 2 lateral bodies, Largest virus. Replicates cytoplasm.
Variola Major (15-40% mortality): Inhalation viremia -> virus enters upper respiratory tract goes to lymphatics.
2° viremia -> infects dermal tissues and organs
Variola Minor (1% mortality)
Transmission: respiratory aerosols+ direct contact
Eradicated by vaccine
Measles
(Paramyxoviridae): (-) sense linear nonsegmented ssRNA virus
contains RNA dependent RNA polymerase, allowing txn
replicates cytoplasm, enveloped, contains virion assoc. enzymes (fusion protein).
Photophobia, 3 Cs: Cough, Coryza and Conjunctivitis.
Koplik spots resemble white grains of salt on oral mucosa
maculopapular rash from behind ears down
giant cell pneumonia (kids w/leukemia or AIDS).
Rare but serious complicationàSubacute sclerosing panencephalitis (CNS degenerative disease).
Live vaccine: single strain MMR
Mumps
(Paramyxoviridae): (-) sense linear nonsegmented ssRNA virus (contains RNA dependent RNA polymerase, allowing txn)
replicates cytoplasm, enveloped, contains virion associated enzymes (fusion protein)
Parotiditis = inflammation of parotid glands (near the ear),
Orchitis (in adults: can cause sterility)
Meningoencephalitis
Live vaccine MMR
Influenza
(-) stranded RNA virus, enveloped, 8 segments
Influenza A: people and animals || B & C: people only
Transmission = Respiratory droplets
Once established as infection -> Destroy ciliated columnar
Hemagglutinin: entry of virus into cells, bind sialic acid
Neuraminidase: access to epithelial cells by liquefying mucus so virus can enter cells
M2 protein= effects ion channel present on virus envelope
Once virus is inside, change the pH drops to 5.5 => Allow release of nuceloacaspid into cytoplasm
Now in cytoplasm kill/damage cells, cilia removed, virus get to lungs and cause primary pneumonia
Virus interferes w/respiratory tract “clearing” mechanisms
Influenza Treatment
Treatment:
Amantadine and rimantadine: block M2 ion channel, against Influenza A, teratogenic
Neuroaminidase inhibitors: Tamiflu (given 1st 48 hours, patient over 1 year) and Zanamivir (given 1st 48 hours, patient over 5 years)
Influenza: Drift and Shift
Antigenic Drift: random mutations, evade immune system, need flu vaccine every year, Influenza A and B undergo drift responsible for epidemics
Epidemic: H1N2 -> H2N2
Antigenic Shift: abrupt major change in antigenicity of a virus, recombo of genes, 1918 Influenza A pandemic, 2 diff strains infect same cell and create new highly pathogenic human flu strain
Pandemic: H3N2 + H5N1 -> H5N2
VZV
HHV-3, enveloped DNA virus (+), dsDNA, Icosahedral symmetry, replicated in nucleus, Herpesvirus
Transmission: very contagious, spread respiratory aerosols + skin contact.
1° viremia starts in respiratory tract spreads to blood & lymphatics.
2° goes to skin -> vesticulopapular rash = chicken pox
Latent in dorsal root ganglion -> can spread along neural pathways to the skin = shingles
Chicken pox (varicella): maculopapular rash (severe on trunk and extremities) -> can lead to necrotizing fasciitis (caused by strep and staph aureus secondary to chicken pox)
Zoster/shingles: affects only one side of the body because a single dermatome is affected (severe pain in nerves precedes lesions
Vaccine: VZV vaccine (live, attenuated)
Influenza
(-) stranded RNA virus aka orthomyzovirus, enveloped, 8 segments
Influenza A: people and animals || B & C: people only
Transmission = Respiratory droplets
Once established as infection -> Destroy ciliated columnar
Hemagglutinin: entry of virus into cells, bind sialic acid
Neuraminidase: access to epithelial cells by liquefying mucus so virus can enter cells
M2 protein= effects ion channel present on virus envelope
Once virus is inside, change the pH drops to 5.5 => Allow release of nuceloacaspid into cytoplasm
Now in cytoplasm kill/damage cells, cilia removed, virus get to lungs and cause primary pneumonia
Virus interferes w/respiratory tract “clearing” mechanisms
Hanta
Bunyaviridae
Transmitted -> vector = Rodent feces (not mosquito)
Infection of lungs = cough, myalgia, tachycardia, pul edema, hypotension
Edema that fills lungs with fluid suffocation of patient
High mortality (50%)
Location: 4 corners (UT, AZ, NM, CO)
Rotavirus
Reovirus
infant diarrhea = reoviridae
Enteric virus -> infect GI (can spread to CNS)
Yellow Fever Virus
Flavivirus
(mosquitoes, presentation)
Hepatitis = jaundice, degeneration of liver
High mortality rate (50%) (Ebola)
Clinical -> Massive gastrointestinal hemorrhages black vomit
Transmission: Mosquitoes
